From patchwork Sat Mar 2 08:25:27 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bibo Mao X-Patchwork-Id: 13579486 Received: from mail.loongson.cn (mail.loongson.cn [114.242.206.163]) by smtp.subspace.kernel.org (Postfix) with ESMTP id C615117561; Sat, 2 Mar 2024 08:25:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=114.242.206.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709367940; cv=none; b=XVsRTa/KljZ69hV51dA/wX4iW1S48bw5cHlgmQhoRxeOIAga9xBPeYIH4FbBLKeJGRA/zpyp64pwzA8qBN5IkDc18zQqdyHwgNAPOB3rgu5SYUagUTECm0tCF/vfaxXBGFmEHdudNVxqUE8lYDHtvNydNTSdFRK3ZLuMnZiCDtg= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1709367940; c=relaxed/simple; bh=AIgU3C1lGFAHJETtO9EJyAbpUdgl6hQx0pIjXkFE8XY=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=u2yDJcMsBJqXbY73Lu8F/TpPoklvPbqNjuYgrOAROHgU3dKUpvi9bjjmYY8WB01XOPmL1arU7AedzXdQ3ACxnfjISB5OQynx0tJ7N7wngTQ9K4MZX8Lh4B/9fqzzs+p9oc9hi8lpY8pd/G4s86FhIqI19TxEv5SbH7wStQCjLBw= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn; spf=pass smtp.mailfrom=loongson.cn; arc=none smtp.client-ip=114.242.206.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=loongson.cn Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=loongson.cn Received: from loongson.cn (unknown [10.2.5.213]) by gateway (Coremail) with SMTP id _____8DxmfCA4uJlF4oTAA--.49896S3; Sat, 02 Mar 2024 16:25:36 +0800 (CST) Received: from localhost.localdomain (unknown [10.2.5.213]) by localhost.localdomain (Coremail) with SMTP id AQAAf8CxLBN84uJlqlhMAA--.6847S4; Sat, 02 Mar 2024 16:25:35 +0800 (CST) From: Bibo Mao To: Huacai Chen , Tianrui Zhao , Juergen Gross , Paolo Bonzini , Jonathan Corbet Cc: loongarch@lists.linux.dev, linux-kernel@vger.kernel.org, virtualization@lists.linux.dev, kvm@vger.kernel.org Subject: [PATCH v6 2/7] LoongArch: KVM: Add hypercall instruction emulation support Date: Sat, 2 Mar 2024 16:25:27 +0800 Message-Id: <20240302082532.1415200-3-maobibo@loongson.cn> X-Mailer: git-send-email 2.39.3 In-Reply-To: <20240302082532.1415200-1-maobibo@loongson.cn> References: <20240302082532.1415200-1-maobibo@loongson.cn> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-CM-TRANSID: AQAAf8CxLBN84uJlqlhMAA--.6847S4 X-CM-SenderInfo: xpdruxter6z05rqj20fqof0/ X-Coremail-Antispam: 1Uk129KBj93XoWxWr1kWrWfuFyDGrW5tF1fGrX_yoW5tr47pF 93Crn5GF48GryfCFy3K34qgr13ArZ7Kw12gFWak3y5AF12qF1Fyr4kKryDZFy5Ja1rZF1S gFs3tr1Y9F4UJ3XCm3ZEXasCq-sJn29KB7ZKAUJUUUUd529EdanIXcx71UUUUU7KY7ZEXa sCq-sGcSsGvfJ3Ic02F40EFcxC0VAKzVAqx4xG6I80ebIjqfuFe4nvWSU5nxnvy29KBjDU 0xBIdaVrnRJUUUBSb4IE77IF4wAFF20E14v26r1j6r4UM7CY07I20VC2zVCF04k26cxKx2 IYs7xG6rWj6s0DM7CIcVAFz4kK6r126r13M28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48v e4kI8wA2z4x0Y4vE2Ix0cI8IcVAFwI0_Gr0_Xr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI 0_Gr0_Cr1l84ACjcxK6I8E87Iv67AKxVW8Jr0_Cr1UM28EF7xvwVC2z280aVCY1x0267AK xVW8Jr0_Cr1UM2kKe7AKxVWUtVW8ZwAS0I0E0xvYzxvE52x082IY62kv0487Mc804VCY07 AIYIkI8VC2zVCFFI0UMc02F40EFcxC0VAKzVAqx4xG6I80ewAv7VC0I7IYx2IY67AKxVWU tVWrXwAv7VC2z280aVAFwI0_Cr0_Gr1UMcvjeVCFs4IE7xkEbVWUJVW8JwACjcxG0xvY0x 0EwIxGrwCY1x0262kKe7AKxVWUtVW8ZwCF04k20xvY0x0EwIxGrwCFx2IqxVCFs4IE7xkE bVWUJVW8JwCFI7km07C267AKxVWUtVW8ZwC20s026c02F40E14v26r1j6r18MI8I3I0E74 80Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcVC0 I7IYx2IY67AKxVW8JVW5JwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF04 k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26F4j6r4UJwCI42IY6I8E87Iv6xkF 7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjxU46RRDUUUU On LoongArch system, there is hypercall instruction special for virtualization. When system executes this instruction on host side, there is illegal instruction exception reported, however it will trap into host when it is executed in VM mode. When hypercall is emulated, A0 register is set with value KVM_HCALL_INVALID_CODE, rather than inject EXCCODE_INE invalid instruction exception. So VM can continue to executing the next code. Signed-off-by: Bibo Mao --- arch/loongarch/include/asm/Kbuild | 1 - arch/loongarch/include/asm/kvm_para.h | 26 ++++++++++++++++++++++++++ arch/loongarch/include/uapi/asm/Kbuild | 2 -- arch/loongarch/kvm/exit.c | 10 ++++++++++ 4 files changed, 36 insertions(+), 3 deletions(-) create mode 100644 arch/loongarch/include/asm/kvm_para.h delete mode 100644 arch/loongarch/include/uapi/asm/Kbuild diff --git a/arch/loongarch/include/asm/Kbuild b/arch/loongarch/include/asm/Kbuild index 93783fa24f6e..22991a6f0e2b 100644 --- a/arch/loongarch/include/asm/Kbuild +++ b/arch/loongarch/include/asm/Kbuild @@ -23,4 +23,3 @@ generic-y += poll.h generic-y += param.h generic-y += posix_types.h generic-y += resource.h -generic-y += kvm_para.h diff --git a/arch/loongarch/include/asm/kvm_para.h b/arch/loongarch/include/asm/kvm_para.h new file mode 100644 index 000000000000..d48f993ae206 --- /dev/null +++ b/arch/loongarch/include/asm/kvm_para.h @@ -0,0 +1,26 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _ASM_LOONGARCH_KVM_PARA_H +#define _ASM_LOONGARCH_KVM_PARA_H + +/* + * LoongArch hypercall return code + */ +#define KVM_HCALL_STATUS_SUCCESS 0 +#define KVM_HCALL_INVALID_CODE -1UL +#define KVM_HCALL_INVALID_PARAMETER -2UL + +static inline unsigned int kvm_arch_para_features(void) +{ + return 0; +} + +static inline unsigned int kvm_arch_para_hints(void) +{ + return 0; +} + +static inline bool kvm_check_and_clear_guest_paused(void) +{ + return false; +} +#endif /* _ASM_LOONGARCH_KVM_PARA_H */ diff --git a/arch/loongarch/include/uapi/asm/Kbuild b/arch/loongarch/include/uapi/asm/Kbuild deleted file mode 100644 index 4aa680ca2e5f..000000000000 --- a/arch/loongarch/include/uapi/asm/Kbuild +++ /dev/null @@ -1,2 +0,0 @@ -# SPDX-License-Identifier: GPL-2.0 -generic-y += kvm_para.h diff --git a/arch/loongarch/kvm/exit.c b/arch/loongarch/kvm/exit.c index ed1d89d53e2e..923bbca9bd22 100644 --- a/arch/loongarch/kvm/exit.c +++ b/arch/loongarch/kvm/exit.c @@ -685,6 +685,15 @@ static int kvm_handle_lasx_disabled(struct kvm_vcpu *vcpu) return RESUME_GUEST; } +static int kvm_handle_hypercall(struct kvm_vcpu *vcpu) +{ + update_pc(&vcpu->arch); + + /* Treat it as noop intruction, only set return value */ + vcpu->arch.gprs[LOONGARCH_GPR_A0] = KVM_HCALL_INVALID_CODE; + return RESUME_GUEST; +} + /* * LoongArch KVM callback handling for unimplemented guest exiting */ @@ -716,6 +725,7 @@ static exit_handle_fn kvm_fault_tables[EXCCODE_INT_START] = { [EXCCODE_LSXDIS] = kvm_handle_lsx_disabled, [EXCCODE_LASXDIS] = kvm_handle_lasx_disabled, [EXCCODE_GSPR] = kvm_handle_gspr, + [EXCCODE_HVC] = kvm_handle_hypercall, }; int kvm_handle_fault(struct kvm_vcpu *vcpu, int fault)